Short Path Distillation of Cannabis : Cannabinoid Refinement

Distillation is a method of refinement that allows for undesirable impurities to be removed through a process of molecular distillation using thermal & vacuum pressures. Cannabis distillation allows for high potency THC / CBD products, cannabinoids are separated through a Short Path Distillation system

What Is Short Path Distillation?


Short Path Distillation is a technique that creates a distillate using a method of thermal evaporation across a short distance. The SPD process is for refining products with precise boiling points, in this example ; cannabis. Cannabis distillation is the process required to extract high potency cannabinoids. The refinement process involves filtering out all unwanted compounds including inactive components that would taint the end results.

The Process for Using Short Path Distillation with Cannabis.

The process requires some preparation, the base product should first be winterized, allowing you to filter out unnecessary components of the product that don’t need to be refined.  Some lab equipment is essential to complete the process :

  • Vigoreux Short Path Head – The key component for the equipment that separates the cannabinoids in the distillation process.
  • Mantle & Flasks – The Mantle & main flasks are used to hold the base product for distillation.
  • Filtration – A filtration apparatus used to remove excess fats & lipids.
  • Chiller – Temperature controller used to raise & reduce temperatures as needed for evaporation.
  • Vacuum Pump & Controller – Control the vacuum pressure to effect the flow & efficiency of the system.
  • Collecting Flasks & MonoCow – Final distillate product is distributed through the MonoCow & collected in the collection flasks.

Summit Research Tech offers a customizable short path distillation kit that includes all of the base components needed to get you started. Piecing together equipment can cause issues with operation & efficiency, we recommend using high quality gear for this process.

Preparing your Product with Winterization.

The first step of the process is the winterization, essentially this is an alcohol wash to remove fats & lipids. The starting material is placed in ethanol & brought to room temperature than it’s frozen filtering at both stages to remove unwanted compounds.  The filtration process can be repeated as necessary – pulling the fats, lipids & chlorophyll out of the plant with the first passes using a 20-8 micron filter. Once you’re satisfied with the quality of the solution you’re ready to begin the carbon scrubbing process, a higher quality product improves overall efficiency.

Carbon Scrubbing for Additional Refinement Preparation.

Carbon scrubbing is an additional step in preparatory refinement to take out unwanted compounds. Add a carbon based powder to the solution, warm it up, shake it up & allow the carbon to attach to the unwanted material. Pour the solution over a silicate bed, this will separate the carbon from the solution, all remaining unwanted material will stay with the carbon leaving you with a prepped solution ready for refinement.

A more in-depth description of the preparation / filtration process can be found on Summit Research – Advanced Short Path Distillation Techniques

Rotary Evaporation to Remove Alcohol & Separate Cannabinoids.

Rotary evaporation is the process used to evaporate the alcohol out of the solution. A flask is filled with the solution, which is suspended & spun through a hot water bath. The solution than creates a thin film on the inside of the flask that improves evaporation rates. By controlling the heat & vacuum throughout the system the alcohol can be separated from the solution. Pour the final solution into the receiving flask & prepare it for distillation.

Refining the Solution with Short Path Distillation.

Distilling your product allows you to extract high potency cannabinoids & remove all of the unwanted compounds. The distillation process evaporates the solution through an SPD unit where a final product is collected in the flasks at the receiving end. A vacuum pulls the vapors boiled off of the solution through the system, separating the alcohol & any remaining unwanted compounds from the cannabinoids. These compounds will be collected during the beginning processes of the distillation before the finished product.

Cannabinoids have a very precise boiling point, which is where utilizing the correct equipment is crucial. The distillation process requires you to dial in the boiling points, which vary depending on the cannabinoids that are targeted – it may take several attempts to figure out the correct boiling points. The best way to understand short path distillation is to get hands on experience, understand the temperatures & watching the reaction as they travel through the distillation head.

The final stage of distillation is where you will collect the finished product, remove the receiving flask with the main body of cannabinoids. Attach another receiving flask to collect the remaining (darker colored) cannabinoids, the tails, which can be refined later on. The final result will be a purified distillate product with high potency of targeted cannabinoids.